<!DOCTYPE html>
<html lang="en">

<head>
    <meta charset="UTF-8">
    <meta http-equiv="X-UA-Compatible" content="IE=edge">
    <meta name="viewport" content="width=device-width, initial-scale=1.0">
    <title>盒子阴影</title>
    <style>
        .shadow {
            width: 200px;
            height: 200px;
            margin: 100px auto;
            background-color: pink;

        }

        div:hover {
            /* x偏移量 | y偏移量 | 阴影模糊半径 | 阴影扩散半径 | 阴影颜色 */
            box-shadow: 10px 10px 10px -4px rgba(0, 0, 0, .3);
        }
    </style>
</head>

<body>
    <div class="shadow">

    </div>
</body>

</html>